Suppose you’re about to undergo a complicated surgical procedure to remove an embolism in your carotid artery. The chief surgeon tells you that he has a new high-powered laser that is great at dissolving clots. Sounds great, right? But when you ask if the operation is...

Everyone who wants to delve into predictive modeling in medicine starts out studying linear regression. After learning the basics we’re told that that this type of model is unrealistic, as associations between biologic characteristics and health outcomes are almost...

At the SAS Global Forum in April CEO Dr. James Goodnight unveiled a stunning new platform for SAS, called SAS Viya. The demos of Viya were amazing, but could the actual product stand up to rigorous testing by power users? Prescient’s Dr. Andrew Kramer got to do an...

Gerardus Mercator (1512 – 1594) was a 16th century polymath who created the world’s first atlas, produced a novel way of plotting latitude and longitude that is still being used today (Mercator’s Projection), and wrote the first book on the italics...

First things first. I have never been employed by SAS and have no commercial relationship with the company. The opinions below are purely my own. Take a look at any of the polls querying which tools data scientists report using. Highest on the list would probably be...

Predicting a true positive event (e.g. morbidity, mortality, adverse event) provides a different epidemiological, financial, and emotional response than predicting a true negative. It follows that having a large number of false negatives might be worse than a model...

(NB: There are many ways to gauge “performance”. In this article I focus on the mortality rate, although the ideas presented herein could be applied to other outcomes.) Hospital A is a large, academic, urban hospital, whose mortality rate in 2015 was 14%. Hospital B...

Length of stay is one of the most frequently used metrics for quality measurement in intensive care units (ICUs). Its definition is deceptively simple: discharge date-time minus admission date-time. There are varying opinions about when admission to the ICU begins and...

In predictive models of binary outcomes such as mortality, the two areas of model accuracy can be loosely described as calibration and discrimination. Calibration measures prediction accuracy across the range of predictive values. Discrimination is a model’s...

Think of the archetype Western movie. Beleaguered town folk out of desperation ask a nefarious character to restore law and order. While a few residents have concerns about the new sheriff, most are satisfied with getting somebody, anybody for protection. What...